S13 SR Oil Pressure question/discussion/issue

[homeslicej2]

Post is updated below


At idle (~900rpm), engine temp ~180*F, under no-load. ~12.5 psi. The needle will fall slightly below this line (i guess about 11psi) at times.


At 3200rpm, engine temp ~180*F, under no-load. I'd say this is ~56psi b/c it's near the middle (a bit over) of the 50 & 62.5psi marks.


The valvecover shot is at idle, ~180*F, & under no-load. It was hard to get a good shot, but you can see an ~1/4" wide strip of oil on the cam lobe. The oil is coming out of the rail in very thin, but continuous, lines. You can barely see the lines in the pic, but they are there. The FSM for S14 SR states w/engine at normal operating temp, under no-load, & gauge installed in place of factory oil pressure switch "more than 11psi at idle & between 46-57psi at 3200 rpm under no-load. If difference is extreme, check oil passage & oil pump for leaks" There is a thin film of oil on the side of the oil pump where it mates to the block around the A/C compressor bracket, but that's it as far as "leaks" go. My gauge sensor is installed in the factory location on a T-fitting along with the factory sensor. So, it's in the right spot. The gauge reads ~80psi at WOT w/engine ~180*F. I have seen in other threads on here (meaning I've searched, used Google too) & while talking to SR owners, that some of them run about this pressure at idle, some run 20psi+. Most all run similiar #'s to me at WOT & while cruising. I use Mobil 1 Extended Performance & these psi #'s are on 10w-30. I have a new, stock oil pan as well. I just want to know if this is normal/average. I want to stop driving my car if it's not. If the oil pump or bearings were going out, wouldn't I have lower pressure throughout the RPM range & also not read near the top-end of the 3200rpm test? I know it could just be the cheaper gauge as well. I want a new one that is full sweep, but I'd like to stick w/Autometer since I have two more ultralight gauges & bc I can get replacement parts from Summit Racing here in GA. Any suggestions on this?

EDIT:

This is a Harbor Freight oil pressure check gauge ($9.99). I know it's not a great one, but it was the only one I could find on short notice. None of the parts stores had one.

Same parameters as 1st pic and Autometer gauge showed same pressure as before. When revved to 3200rpm, it was bouncing b/t 60 and 68 psi. gauge was installed in T-fitting (along w/autometer & stock sensors) off of factory sensor location. Guess I'm good.

[homeslicej2]

No one has any input?

[almost heaven]

It's been a year and a half since mine was running, so I don't recall idle and WOT #s. I hope to be able to let you know what I show, soon. I think a leak would have to be pretty big to affect pressure.

[surfer240]

mine looks similar to that 10-11 idle and 50ish crusin like 75 psi on a cold start... i removed my sensor to put in the gauge does this matter? i think it is jus for the bulb on the cluster

[homeslicej2]

yeah, stock sensor is for the light in the cluster. I can't remember at what psi the sensor lights up the low oil pressure light. I think it's 5psi or something like that. Also, my stock sensor is still hooked up and working (as far as I know) but isnt' on.

EDIT: Added new pic. I guess I'm good.

[homeslicej2]

So, I decided to relocate the oil pressure sender. I bought a 3ft -3AN Autometer line from Summit Racing and a new oil pressure sender. I mounted it up high on the engine bay sheet metal b/t the shock tower & wiper motor; even with it being up high & having to fill a 3 ft hose that adds ~1cm3 (I did the math lol) of space for the oil to fill, after driving it for 30+ minutes & giving an early 2000's Mustang GT a spanking, the gauge never dropped more than just a bit below the 25psi mark (probably the 20 psi that the mech. check gauge showed). I have come to the conclusion that having the Autometer sender mounted at 90 degrees in an adapter causes it to read incorrectly. Sender was T'd off of an adapter, see my "how to install an oil pressure sender" thread if you're curious about the adapter; I will also update that thread w/this install asap.